I know we would not say a 3 months period, but why exactly? Is it because period is noncount? But why is it correct to say a period of 3 months
How do you know when to pluralize nouns and when not to? Is there a website that breaks down examples like period for me?
Thank you!
3-month period. Note the hyphen. – Tushar Raj May 12 '15 at 14:44